Fluorescent microscopy has revolutionized modern biology. From calcium sensitive dyes that track the exquisite regulation of this second messenger to fluorescent fusion proteins that allow us to pinpoint the subcellular distribution of proteins, our ability to observe the inner workings of a cell is constantly expanding. To take advantage of the benefits of these advances we require state-of-the-art microscopy tools. Our current demand for confocal microscopy has exceeded our capacity and our current technology. We are requesting funding for a Zeiss LSM 710 confocal microscope to support our investigation of diverse aspects of developmental and cellular biology with biomedical applications. This microscope was selected as the most capable laser-scanning microscope that can support the research projects of our users, which include biologists with developmental, cellular, and tissue engineering research areas. Moreover, this microscope is modular and expandable to support future applications, including those not yet envisioned. The LSM 710 has incorporated several improvements over previous Zeiss versions, including higher sensitivity, reduced background noise, improved flexibility for new fluorochromes, and integrated analytical methods and is thus ideally suited for the needs of our expanding group of NIH- funded investigators at Rice University.